alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET EXPLOIT Zimbra <8.8.11 - XML External Entity Injection/SSRF Attempt (CVE-2019-9621)"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/autodiscover"; nocase; http.request_body; content:"<!DOCTYPE"; depth:50; content:"file:///etc/passwd"; distance:0; fast_pattern; content:"<EMailAddress>"; content:"<AcceptableResponseSchema>"; reference:url,www.exploit-db.com/exploits/46967; reference:url,packetstormsecurity.com/files/152487/Zimbra-Collaboration-Autodiscover-Servlet-XXE-ProxyServlet-SSRF.html; reference:cve,2019-9621; reference:cve,2021-2109; classtype:attempted-user; sid:2031562; rev:1; metadata:affected_product Web_Server_Applications, attack_target Client_Endpoint, created_at 2021_01_27, cve CVE_2021_2109, deployment Perimeter, confidence Medium, signature_severity Major, updated_at 2021_01_27;)